The 23-year-old England international penned a long-term deal with the Gunners after Arsenal agreed a £16m fee with the Red Devils on transfer deadline day.
Welbeck had fallen out of favour at Old Trafford over the past season and Radamel Falcao’s loan inevitably resulted in the forward leaving 20-time English champions.
Arsenal manager Arsène Wenger had been looking to bolster his attacking line-up over the past week after Olivier Giroud was sidelined for three to four months with a broken leg.
And Arsenal’s club-record signing Ozil took to Twitter to welcome Welbeck to the FA Cup winners and back the former Sunderland striker to score plenty of foals for Wenger’s side.
Ozil wrote: “I’m glad to welcome you, Danny! wish you as much goals as possible! #WelcomeWelbeck #NewStriker #No23 #COYG”
Welbeck scored 20 goals in 92 Premier League appearances for the Red Devils.
The striker, who is currently on international duty with England, could make his debut for the Gunners in the Premier League home match against Manchester City on 13 September.
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